Improvement in try-squares



W. F. ARNOLD.

Try-Squares.

Patented April 22, 1873.

UNITED S ATES PATENT OFFICE;

WILBUR F. ARNOLD, OF WINTHROP, CONNECTICUT.

IMPROVEMENT IN TRY-SQUARES.

Specification forming part of Letters Patent No. 138,113, dated April 22, 1873; application filed October 26, 1872.

To all whom it may concern:

Be it known that I, WILBUR F. ARNOLD, of Winthrop, in the county of Middlesex and State of Connecticut, have invented a new Improvement in Try- Squares; and I do hereby declare the following, when taken in connectionwith the accompanying drawing and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawing constitutes part of this specification, and represents, in-

Figure 1, a side view; Fig. 2, a vertical central section on line a; w,- Figy3, the cam detached; and in Fig. 4, an end view of the pin.

This invention relates to an improvement in method of securing the blades into the handles of try-squares, the object being to enable the user to readily remove or tighten the blade, as occasion may require; and it consists in combining, with the handle and blade, a pin, which extends through the handle and blade, formed with an eccentric or cam-shaped portion, which, when the blade is set in place and turned, will bear upon or force the blade hard down and secure it in its proper position.

A is the handle, and B the blade, of the usual form for try-squares. Through the ban dle a pin, C, is passed, as seen in Fig. 2, a shoulder or its equivalent thereon forming a seat to govern its position; and on the said pin, in position corresponding to the blade B, is formed a groove or cam, a, by preference of an eccentric form but the form is immaterial. Passed through the handle and blade, the form of the pin, as seen in Fig. 4, allowing it so to do, the pin is turned until the cam bears hard upon the lower edge of the opening through the blade, pressing it hard down upon its seat, as seen in Fig. 2, securely holding it in position.

The advantages of this construction over the rivets commonly used are, first, that it is very much cheaper; and, second, if the common try-square falls the blade is liable to be loosened in the handle, and to tighten or readjust it is a very difficult operation; but by this invention, should the blade become loosclaiming screws extending through'the handle and tongue of a try-square, and of a camshaped body, so as to adjust the tongue to the desired angle, as such is not new.

I claim as my invention In combination with the handle and blade of a try-square, the pin C, constructed with a cam, a, substantially in the manner described, to secure the blade in the handle without the necessary intervention of other pins or their equivalent.

WILBUR F. ARNOLD.

Witnesses EDGAR W. ARNOLD, DAVID SnIvERIcK. 

